1. Field of the Invention
The invention is directed to a small class of esters useful in the treatment of certain viral infections. Additionally, the invention involves topically acceptable formulations of these esters and method of utilizing same.
2. Description of the Prior Art
In U.S. Pat. No. 4,138,562, issued Feb. 6, 1979, and J. Med. Chem., 20, 612 (1977), I disclose the synthesis of the nucleoside 9-[2.alpha.,3.beta.-dihydroxy-4.alpha.-(hydroxymethyl)cyclopent-1.alpha.-y l] which will hereinafter be referred to more simply as C-Ara-A or cyclaradine (Compound 1). Cyclaradine is the parent alcohol of the alkoxyalkanoate esters of this invention. This alcohol and the simple alkanoate esters are the subject of my copending application Ser. No. 1,072, filed Jan. 5, 1979, now U.S. Pat. No. 4,268,672.
Cyclaradine exhibits potent antiviral activity in vitro against viral pathogens such as Herpes and is resistent to the enzyme adenosine deaminase (a normal constituent of human serum) which is responsible for the destruction of the antiviral properties of currently available antiviral nucleosides such as 9-.beta.-D-arabinofuranosyladenine (Ara-A). It has subsequently been found, however, that cyclaradine and its simple alkyl esters are significantly less active in vivo.